For typical aircraft doors, such as cargo doors, the actuating forces or loads transmitted by the linear actuator 3 to the beam 1 and, thus, to be absorbed by the beam 1 and to be distributed to the cross beams 2 reach values of e.g. 11 tons. These loads do not only comprise load components acting in the y direction, which load components tend to bend the beam 1, but, due to the pivoting movement in the yz plane, also load components which transmit an angular momentum to the beam 1 and, eventually, to the cross beams 2. In other words, the actuator fitting or beam 1 is loaded by a bending force in the y direction and by a torque or torsional momentum, and the respective loads are applied at the bearing 9 of the beam 1, which bearing 9 supports the casing 4 and provides the rotation axis 10 for the casing 4.
Therefore, in order to avoid failure the actuator fitting or beam 1 must be a very massive and strong component, which is typically made of titanium and its attachment to the cross beams 2 likewise must be very strong. Meeting these requirements is costly and adds significant weight to the aircraft.